Method of treating wood



Patented Oct. 17, 1939 METHOD OF TREATING WOOD Russell Fortune, Indianapolis, Ind.

, No Drawing. Application February 1, 1937,

Serial No. 123,555

Claims.

This invention relates to a new composition of matter made from natural wood. More particularly, this invention relates to a method for producing cellulosic compositions of matter from natural wood, which conform to the natural wood in grain structure, but differ from it in composition, texture and appearance.

Natural wood is a. complex substance of which the constituting components have never been fully determined. It is the present theory that natural wood consists primarily of cellulose and lignin. The structure of the cellulose molecules and the way in which the are united are not 50 or figure.

known. The term lignin is used, in general, to characterize the portions of the wood other than cellulose. While this description of the nature of wood is a broad generalization which attempts to comprehendmany conflicting chemical theories as to the nature of wood, still it is adequate for the purpose of explaining this invention to the extent permitted by the present knowledge of wood chemistry.

Wood is used not only for many structural purposes but likewise etensively for decorative effects. Furniture and wood paneling are outstanding examples of the use of wood for this latter purpose. Natural wood, however, has some very definite limitations, both from the point of view of the interior decorator, and the cabinet and furniture manufacturer. In the first place, the color of any given piece of wood is the result of the operation of nature andwaries with the specie of tree, its age, the soilin' which it grew, climatic conditions which prevailed during its growth, and the portion of the tree from which it was cut. It has been conventional to stain woods variously but in each case the original color of the natural wood hasdmposed a limitation on the color range to .-Which it could be stained. Also, from the point of view of the manufacturer, it has always beendi flicult to match woods so that supplying additional pieces or replacing pieces in a given furniture suite was possible.

Of late, there has been a decided trend toward painted wood because the latter inherently avoids the limitations of naturalwood as to color. The painting of wood, however, sacrifices its greatest feature of natural beauty, the inherent pattern Modern interior decoration requires greater latitude and delicacy of color than is possible in natural wood and on this account attempts have been made to substitute synthetic resins or metal products for wood, in furniture, paneling, and the like. However, products of this nature are cold, hard and lacking in natural beauty so that interiors done in these newer materials usually seem impersonal, and cold or unhome-like.

The wood products of this invention retain the character of the natural wood and hence its inherent wood-like quality, but on the other hand are not limited by the natural color of the wood. These products are derivatives of natural wood which retain the cellulosic orientation of the natural WOOd fiber. They are so modified chemically and/or physically as to other components that a section presents a surface radically different from ordinary wood in appearance, and appeal to the eye. Otherwise expressed, the products of the invention comprise the cellulosic components of natural wood disposed in relation to one another as by nature, but substantially divested of pigmented lignin. The term pigmented lignin is used herein to describe natural colors occurring in the wood, whether they be actual components of the lignin itself or dyestufis of nature deposited in the wood. The pigmentation of wood is no better understood than the chemistry of the lignin (concerning which little is known), and, moreover, the nature of the pigmentation seems to vary from one specie of wood to another. However, by the process of this invention, these products may be made from a great variety of woods including oak, maple, beech, aspen, mahogany, prima vera, ash, koa, Oriental wood, red wood, bubinga, poplar, American walnut, madrone, Australian silkwood, silky oak, and other woods native to various parts of the world.- In all cases the products of the process are characterized by the substantial absence of pigmented lignin, an absence which imparts a characteristic sheen to the cellulosic structure and paves the way for any desired artificial pigmentation or coloration. Therefore, the terminology natural wood cellulosic structure substantially divested of pigmented lignin is intended to comprehend not only wood products which are substantially colorless, but also products which have an artificial color which is independent of the original wood color. The terminology is likewise used to distinguish the products of this invention from ordinary paper, which is a cellulosic structure divested of pigmented lignin but is not the natural wood cellulosic structure inasmuch as the latter is destroyed in the pulping operation.

Since.the products of the process of the present invention are manufactured from natural wood and since the chemical components of the latter have not been accurately determined, it is impossible to describe these products as compositions of matter except in relation to the properties of the natural wood from which the products are derived. Since each variety of natural wood differs chemically from each other variety, and since each specimen of each variety differs from other specimens from difierent'trees of the same variety, it is necessary to make a, comparison between samples of wood treated to provide the products of this invention and untreated samples of wood.

Natural wood is characterized by the fact that it is differentially pigmented, these dlfierences of pigmentation dominating the visual eiiect commonly called the wood pattern. Ir a sample of almost any variety of wood be examined carefully, it will be observed that the pattern is primarily constituted by variations of color ranging from a light red, brown or yellow through darker browns, reds to black, the particular range in each case being determined by the nature of the wood. Many varieties are of reddish tone or vary from red to red-brown. The products of this invention on the contrary are usually a substantial monotone as to color. However, the character of the wood, particularly if it be pronounced, stands out by virtue of variations in the fiber structure of the wood which causes certain portions of the surface to reflect and absorb light difierently. While difierential light reflection and absorption exists in natural wood, this factor is subordinated from the point of view of appearance by the color intonation. When this latter factor is removed, the appearance of the wood is dominated by the variegations of the relatively light reflective and absorbent areas.

While it is difiicult to ofier complete and adequate explanation of the difference between the appearance of the wood products of this invention and natural wood, and particularly the aesthetic efiect, still certain definite changes in light reflectivity have been noted and are mentioned as proffer and partial explanation.

The wood products of this invention (unless artificially colored) have a higher .coefiicient of light reflection than the original wood from which they are made. As a result the pattern of the wood may provide greater contrasts of reflection and absorption than is possible when the coefficient of reflection is lower. On this account, the pattern of the wood in many specimens stands out very strikingly to the eye. This increase in the coefiicient of reflection takes place, to a substantial extent, in the green to yellow chromatic wave lengths, the range to which the retina of the eye is most sensitive. Therefore, the wood products of this invention, while characteristically wood-like because of the accentuation of the wood pattern, still have a characteristic appearance of their own due to their relatively high coeficient of reflection in the chromatic range to which the eye is most sensitive. On this account the products appear live, interesting, scintillating or stimulating in comparison with the more subdued appearance of natural wood.

The products, when not artificially colored, have a sheen and luster akin to that of mercerized cotton, rayon or satin, and whether the effect be due to a more translucent nature of the surface or the greater coemcient oi reflection in the color ranges to which the eye is particularly sensitive, still the fact remains that the surfaces are more arresting and interesting to the eye than ordinary wood surfaces.

Unless artificially pigmented, the wood prod= ucts of this invention are more translucent than the materials from which they were made and on this account the surfaces have the appearance of greater depth. The difierence between the transparency or translucency of the products of this invention and corresponding properties of natural wood are accentuated if thin sections be soaked in water. In the case of natural wood,

the transparency or translucency is not materially afiected, whereas the products of this invention transmit light to a very marked degree when wet out with water. In many of the products, bewildering light efiects which cannot accurately be described, take place at the surface. For instance, a given portion of the wood appears white when light is reflected from it on one angle, and pale yellow or gold from another angle. On some specimens the grain seems to stand out in white and cream in a given light, but on changing the angle of light the design reverses and the pertions which seemed cream become white, and vice versa. With many varieties of wood, for example, maple, the pattern may appear in light and shadow, an efiect which the eye interprets as relief. In fact it is difficult to believe some samples are smooth at the surface, except by touching them.

The products of the process of the present invention are described in detail, and claimed in my copending patent application Serial No. 4,720, filed February 2, 1935, and entitled Cellulosic product of which the present application is a continuation in part. The present application is directed particularly to a process or method by means of which these products are obtained conveniently and economically.

Since these inventions provide products characterized by the pattern of the naturalwood colored to the taste of the designer or decorator, they have application to the veneer field. The method herein described is disclosed particularly in relation to veneer or sheet-like materials as the preferred embodiment of the invention. At the present time cabinet work and paneling is fabricated with veneers because veneer panels are stronger and have less tendency to warp or check than single thickness panels. Also, it is possible to obtain more artistic efiects from veneers because of the facility with which wood patterns may be matched or related.

Veneers, in general, are thin sheets of wood ranging roughly from one-eighth to one onehundredths of an inch in thickness. veneers may be made thicker but such a practice would utilize more of the expensive wood and serve no useful purpose at the present stage of development of the veneer art. Veneer may be made up into veneer panels with other layers of wood (laminated structure) or may be attached under pressure to a solid piece of wood or core. Other types of backing for the veneer may, of course, be employed for example canvas, sheet metal, composition materials, synthetic resins and the like. However, attachment of the veneer to a wooden backing is more common at the present time.

Broadly speaking, the present invention resides in the determination that the highly unusual qualities characterizing the products hereinbefore disclosed are achieved by a process of treating natural wood which is akin chemically but not physically to a paper making process. This process is characterized particularly by the fact that a the ornamental veneers are transposed into cellulosic products substantially devoid of pigmented lignin without structural disorganization of the grain pattern of veneer. Otherwise stated, I have discovered that the products which I have described may be constituted by the mild application of incipient paper making chemical processes which remove ligneous color physically and/or Obviously, I

chemically without disrupting the cellulosic struc- $3 ture. However, in view of the marked difference between .the raw products to which the process of the present invention is applied and the open porous raw woods from which paper is made, as well as the marked difference in the products obtained, the present invention may be defined more accurately as a new art foreign to the art of making paper.

From the broad point of view the present invention comprises the divestiture of the natural pigmentation and ligneous inclusions of natural wood without fiber or cellulosic disorganization.

The components of the wood which are modified or removed are those which are soluble or quasisoluble in a dilute aqueous chemical solution of the type hereinafter discussed. However, since the physical stability or structure of the final product is an important factor (from the point of view of practical utility) the process of the invention involves controls directed primarily to the maintenance of these desired physical characteristics. The process therefore comprises physico-chemical treatment of ordinary wood in which process the physical and chemical controls are interrelated and adjusted to provide a cellu losic product substantially devoid of lignin and natural pigmentation, but structurally intact. For the reason that chemical and physical controls are utilized to achieve the final result, these controls are discussed hereinafter in the orderstated.

Chemical characteristics As I have stated in my copending application hereinbefore referred to, from the chemical point of view the components of the wood which are modified and are removed, are those which are soluble or quasi-soluble in a dilute aqueous solution, the preferred constituting components of which are alkali and chlorine gas.

By reason of the fact that little if anything definitely is known of the chemistry of wood, no attempt is made herein to describe or define in detail the nature of the chemical reaction which takes place in the wood itself. The exact nature of the components removed from the wood by the treatment is a matter of speculation. Apparently, the cellulosic structure of the wood is structurally intact save for a slight shrinkage or contraction. The lignin content in the wood, when subjected to the treatment, apparently undergoes some chemical change or removal. After treatment the wood becomes lighter or even white in color and lustrous in appearance.

'The practical problem is to accomplish the desired chemical transformation without disturbing the physical structure of the wood, and in this respect, the differentiation of the present invention from the ordinary treatment of disintegrated wood or wood of a highly porous variety is apparent.

As a general rule it may be stated that the various types of ornamental wood to which the process of the invention has application, respond differently to different techniques and different degrees of treatment. The problem has been to provide a general type of treatment to which various types of wood do not respond adversely and do not become disorganized, disintegrated or too weak to handle before the transformation is accomplished.

In the practice of the present invention it is preferable to select veneers made from the ornamental woods, which have interesting grain patterns in order that the final products will be more pleasing in appearance and more specifically adapted to the building and fabrication of structural pieces, either for furniture or for paneling. For example, if it is desired to prepare cellulosic products for use in a salon in a store or in a home, of course, preferable to select veneer of a type which will be relatively hard after it has been treated, in order that the final product will not be damaged too easily if bumped or nicked during use, 0n the other hand, it is preferable also to select woods which are not too porous for the reason that such woods are not well adapted to receive protective or ornamental finishes, nor are they usually very interesting insofar as decorative effects are concerned. The types of wood which I have heretofore mentioned are well adapted to processing according to the present method, since these woods after they have been treated are neither too soft for practical use nor too porous to be given a fine finish. In addition to the various types of wood which I have mentioned, others of more exotic variety are adapted to be treated, but these are not discussed in detail for the reason that they are generally too expensive for use except in limited quantities.

After the wood intended to be treated has been selected it is next subjected to treatment; In

this treatment the woods are exposed to the action.

of a treating solution for a period of from four to seventeen hours, more or less, the exact length of the treatment depending upon the type of wood, its thickness, the precise nature of the final product desired and the ratio of square footage of wood to quantity of solution. One example of a solution adapted to use in the practice of the present invention comprises approximately:

Pounds Caustic soda (76%) 10 Soda ash (58%) about 37.5 Chlorine gas. about 5 which is difiused or dissolved in about gallons of water in which the caustic soda and soda ash have been dissolved.

The above example illustrates a type of solution which is generally adapted to the treatment with safety, of a variety of different types of ornamental wood. The precise limits of the quantitles of chemicals dissolved, or the quantities of chemicals equivalent to those mentioned are not disclosed for the reason that the results obtained by adjustments in the quantities of chemicals, or in the substitution of other chemicals in place of or in addition to those mentioned are gradual in variation. For example, the color in terms of whiteness, as well as the physical qualities which identify the final product, are not readily measurable value though the differences may be discernible to the eye. Those skilled in the art will be able-to modify the process to obtain desired results in the treatment of specific varieties of wood or specific cuts of wood of a given variety.

In this respect, the following examples are illustrative A solution adapted particularly to the treatment of American maple comprises about Pounds Soda ash (58%) 76 Caustic soda (76%) 58 Chlorine gas 32 dissolved in about 450 gallons of water in which the caustic soda and soda ash have been dissolved.

For treating woods of a more difdcult nature, for example, prima vera or African walnut,

latter solution, of course, woods such as maple can be and are being treated without danger. The point to be observed is that less time is required to accomplish the intended results. If the alkali content and particularly the caustic soda content is too high. then the woods may be disintegrated. On the other hand, if the quantities of alkali are too small then of course it is diflicult, or impossible to obtain appropriate transposition of the wood into a cellulosic product in any reasonable period of time.

Because of the commercial aspects which are involved, the present invention is disclosed particularly in relation to treatment of the wood with caustic soda, soda ash and chlorine gas as the preferred chemicals constituting the treating bath for the reason that these chemicals are readily available in industry at low prices.

In preparing the treating solutions it is preferable to measure the quantity of water required to constitute a given batch and then dissolve the solid chemicals in the water. The water may be ordinary tap water although it should not contain any unusually large quantity of organic or inorganic coloring matter or components reactive in respect to the chemicals added so as to produce discolorations.

When the chemicals are added the temperature of the water increases about 15 F. more or less. It is preferred to adjust the initial temperature of the water so that the final temperature of the solution, or the temperature of the solution during the period of treatment is around 100 F. Under these circumstances it is preferable to have the water at a temperature of about 7540 F. before the chemicals are added.

In constituting this aqueous solution it is preferred to add the caustic soda and soda ash and then dissolve the chlorine in the solution by means of a diffusion nozzle, or an alumdum or carborundum cup or thimble. This diffuser assists in dispersing the gas, facilitates its solution in the mass of liquid and minimizes the loss of gas through escape from the surface of the liquid.

After the treating solution has been prepared the pieces of wood or the sheets of veneer are disposed in the solution fora period of time until the intended transposition has taken place. The following table is illustrative of the time required to heat various types of wood:

Wood Thickness Time Indies Hour-s Quilted or Oregon maple its 8-12 Maple l's 10-20 Bird's-eye maple yrs 10-20 Hard maple }s 10-20 Soft maple ls 8-12 Prime ver lie 12-18 Sa lli. is: 18-20 S11 y oak $e 18-20 Lovea its 15-20 Sequoia K's 12-18 oa is 12-20 The values in the foregoing table are based upon the treatment of about /2 to 1 square foot of wood to about 1 gallon of solution. In other words, 450 gallons of solution such as that indicated in Example 2 or 3 is adapted to treat from about 225 to 450 square feet of wood of 1/28" thickness. The variation depends upon the nature of the wood. its thickness and the other factors which have been mentioned.

After the wood has been treated for an appropriate period of time, the wood preferably is rinsed for about 2 hours, in a solution of about 110 lbs. sodium bicarbonate in about 450 gallons of water. Next, it is preferred to treat the wood for about one hour in a solution made up of about 3% gallons of about 56% acetic acid and 450 gallons of water. Finally, the wood is rinsed in clear water for about fifteen or twenty minutes. The treatment with bicarbonate solution and the treatment with acetic acid is recommended, not particularly to improve the color of the product after it has been treated initially but rather to improve the physical qualities thereof. These treatments assist in improving the hardness of the wood and its feel. After rinsing with water the product is finally dried as hereinafter discussed, and is ready for use.

Physical characteristics In the practice of the present invention it is preferred to arrange sheets of wood which are to be treated vertically in racks adapted to be raised or lowered into tanks in which the various treating solutions are disposed. The wood should be covered entirely with treating solution and in some instances it is necessary, because of the lightness of the wood, to weight the sheets or the racks to hold them in position. The racks preferably are made of wood or some noncorrosive metal such as Monel metal, and spacer elements between the sheets of wood are used to keep the respective sheets separated from one another. If adjacent sheets of veneer are permitted to remain in contact with one another over long periods of time during the course of treatment, then these areas do not respond uniformly to the chemical treatment and it is particularly difilcult to achieve uniformity of color. It is preferable to space the sheet sufliciently far apart to permit, free ingress and egress of the solution to and from the surface of the adjacent sheets.

The speed at which the treating solution penetrates the wood being treated influences the length of time required to complete the treatment. In the veneers made from close grained woods for example, the rate of penetration is slow. Greater time may also be required to penetrate veneers which are cut in certain ways from logs comprised of wood ordinarily considered to be relatively open and porous. With any given veneer, however, the objective is to obtain veneers which are uniform in'cross section, that is to say, to obtain cellulosic products which are uniform throughout. Obviousl if a piece of wood is simply bleached at the surface then as soon as the wood is sanded slightly, for example, prior to finishing, the dark colored underneath portions are exposed to view and the final appearance is not pleasing.

In the production of veneer products of the present invention the process preferably is carried to the extent necessary to accomplish complete transformation throughout the entire thickness of the natural woods being treated. The adjustment and corelation of the chemical controls necessary to divest very thin veneers of the components to be removed, and the physical controls necessary to insure the production of a product structurally intact and strong enough to be handled are particularly important. With pieces of wood which are relatively thick, the process of thepresent invention may be carried to the extent necessary only to accomplish the transformation to a depth necessary to suit the subsequent requirements of finishing or woodworking.

In the practice of the invention the natural wood being treated is submerged in the solution for the appropriate length of time. During the treating period, at the start of the process, the wood tends to become very dark and sometimes almost black in color. Thereafter the wood gradually becomes lighter in color and the treated product is removed from the bath when the desired color is obtained. With almost all varieties of wood a somewhat slippery feel is imparted to the surface of the wood by the treating solution, and, at the same time a whitish precipitate appears to develop in the solution. The precipitate usually drops to the bottom of the tank. In cases where'the wood contains a large amount of coloring matter, for example, in red wood, the coloring matter diffuses from the wood into the solution and disappears.

After the natural wood has been converted by the process described, and after it is washed in water, it is allowed to' drain and finally is dried. The drying operation preferably is conducted by means of air warmed to a temperature of approximately 150-200 F., more or less. If the temperature during drying is too high then the outside of the wood contracts more than the inner portions and likewise the end sections contract more than the center sections with the result that checking tends to occur. The wood preferably is dried as uniformly as possible until a moisture content of from about 4-7% of water is reached.

In the treatment of wood veneers according to the process of the invention, a given piece of wood undergoes a substantial change in the dimension transverse the grain. For example, a piece of veneer which is twenty inches wide at the start may expand to twenty-two or twentythree inches during the treating process and then contract from twenty-two or twenty-three inches down to seventeen and one-half or eighteen inches during the drying process. Obviously, it is essential that the wood be dried carefully after treatment since the degree of contraction is so great. The loss in width should be taken into account in the selection of particular sheets of veneer for particular uses. As a general rule, it is safe practice to allow one inch for shrinkage for each ten inches of width of wood prior to processing.

The cellulosic veneers of the present invention are thin parchment-dike products, limp when wet, hard when dry, in most cases less brittle than the corresponding natural veneer, and of equal or superior toughness. Peculiarly, the speciflc gravity of these products is usually from 10 to 25% less than the specific gravity of the corresponding natural wood veneers of equal thickness, though the loss of weight varies according to the nature of wood and the degree of treatment.

The preferred products of the invention are preferably one-eighth to one one-hundredth of an inch in thickness and preferably are substantially uniform in composition throughout, The

letter feature precludes the possibility of migration of pigmented lignin within the cellulosic structure.

' Finishing Since white furniture is very much in vogue at the present time, the cellulosic products of the present invention being devoid of color, provide the means for effecting new modes of decoration. Extensive experience has indicated that the products when applied to cores or backings of the type conventionally used in the woodworking industries, are satisfactory in every respect. The panels to which the products are applied as by non-staining gluing methods are manufactured Just as if the panels were surfaced with ordinary wood veneers. A distinct advantage in the production of furniture is provided, however, because of the fact that the cellulosic products of the invention need not be filled with paste fillers or the like prior to finishing. The panels simply are sanded with a fine grade of sandpaper, after which clear lacquer is applied. The sanding does not dull the inherent luster which is characteristic of the veneer facings.

While natural woods which have undergone treatment according to the process of the present invention provide products which are white, or colorless, I have discovered that these products are veryunusual in respect to their capacity to receive artificial pigmentation or coloration. In view of the fact that the products of the invention are superior to natural wood in this respect, the decorator or designer who is using the products of the invention is provided with a material of a fixed white starting color from which he is able consistently to prepare products of a variety of colors which are uniform and which are not less lustrous than'the initial product from which they are made.

One of the means which I have discovered for providing products which are artificially colored is based upon the treatment of the white cellulosic products with relatively dilute aqueous solutions of inorganic salts. According to this treatment, inorganic salts selected for their natural color are dissolved in water to provide a bath into which the white material is immersed for a period of from about 2 to 20 hours. The time of immersion of the white material in the bath depends upon the intensity of coloring desired to be imparted thereto. It is particularly significant to note that the color which the inorganic salt may impart to the water in which it' is dissolved does not in all instances correspond to the artificial coloration imparted to the white material undergoing treatment.

While it is relatively impossible to list all of the chemical salts which are adapted to use for coloration purposes, the following chemicals are disclosed to illustrate this aspect of the invention:

Final color of product Copper sulphate, 16 lbs. to 450 gals. of

water Green. Chrominum acetate, 8 lbs. to 450 gals.

of water Gray. Cobalt sulphate, 10 lbs. to 450 gals. of

water Pink Ferric ammonium sulphate, 8 lbs. to 450 gals. of water Brown. Potassium bichromate, 6 lbs. to 450 gals.

of water Yellow.

When artificial coloration is imparted to the white products of the present invention by means of inorganic salts absorbed from aqueous solutions, the colors of the final products are delicate and feminine in their appearance and the colors themselves are fast and permanent.

When the colors of a more brilliant or positive nature are desired, I have discovered that the acid dyestuffs which are soluble in water possess the capacity to color the white products of the present invention without detracting from the inherent luster or from the interesting appearance of the grain pattern. When the acid dyestuffs are used, aqueous solutions are prepared therefrom, and the white products are immersed in these solutions for periods of from about 2 to 10 or 12 hours, more .or less. One of the most striking colored products of the present invention for example is one colored intense black. The appearance is rather similar to that of polished char coal. The result is achieved by treating the white product with napthylamine.

Red, yellow, gray, tan and copper and metallic eflects, likewise, are provided by the use of acid dyes. In general, I prefer to use approximately 5 ozs. to 20 ozs. of acid dyestuffs to about gals. of water. Solutions of this type possess the capacity to color the products of the invention uniformly throughout.

While many materials persist in the products of the present invention which cannot be identified chemically, still I have determined that the colorability of the products of the invention'are analogous to cotton in its dyeing properties, and, in general, the materials which are used for dyeing cotton may be used for coloring these products either by immersion of the products in solutions, or by application of the colors to the wood by spraying or brushing. Thus, the products of the invention, when artificially colored, provide new possibilities in decoration from the point of view of both paneling and furniture.

Having described my invention, I claim:

1. The method of treating wood veneer to produce an ornamental cellulosic veneer structurally intact but devoid of natural coloration, which method comprises, divesting natural wood veneer of natural pigmentation in an aqueous alkaline solution which containschlorine, without disturbing the fiber organization of the wood.

2. The method which comprises, treating wood veneer in a dilute aqueous solution containing caustic soda, soda ash and chlorine, said components in the solution being adjusted in amount in relation to the wood being treated so that the solution at a temperature not substantially exceeding 100 F., chemically transforms the wood into a cellulosic product structurally intact and substantially devoid of natural pigmentation.

3. The method of treating natural wood veneer to provide a product structurally intact but devoid of color intonation, which method comprises, subjecting wood veneer to a bleaching process for a period of time long enough to divest the wood of its natural color, without disturbing the fiber organization of the wood, in which process the bleaching agent comprises a dilute aqueous alkaline solution containing dissolved chlorine.

4. The process of providing an ornamental cellulosic product which comprises, subjecting wood veneer to a bleaching process with an aqueous alkaline solution containing chlorine for a period of time suflicient to divest the wood of its natural color intonation, but insuiflcient to disturb the fiber organization of the wood, then washing said product, then treating the product in an aqueous solution containing color imparting inorganic chemicals for a period of time sufficient to treat the product uniformly throughout the cross section, then drying said product.

5. The process which comprises subjecting natural wood veneer to an incipient paper-making chemical process by immersing the wood veneer in an aqueous alkaline solution containing chlorine, for a period of time until the veneer becomes limp and is substantially divested of natural pigmentation, then removing the limp veneer from the solution and drying the veneer in supported condition without disturbing the fiber organization of the wood.

RUSSELL FORTUNE. 

